In order to optimizing electron transfer and optoelectronic properties in nanoparticulate thin films for electronics we report on an efficient and fast method for surface functionalizing semiconducting metal oxide nanoparticles in liquid phase using a specific dialysis route. The dialysis process leads to a homogenous surface functionalization of nanoparticles with complex organic molecules: porphyrine derivatives. High resolution transmission electron (HRTEM) images verify the successful bonding of the molecules to the surface of the ZnO nanorods. Emission- and absorption- spectroscopy indicate an effective electronic interaction between the ZnO nanorods and the pophyrine derivatives. In addition, we discuss on the binding mechanism and the ligand exchange kinetics of the porphyrine molecules.